The general objectives guide the proposed work: 1) to conduct a comprehensive national study of the mental health implications of ethnic identification, identity and consciousness among persons of Mexican origin, and 2) to develop a national resource that will include drawing a national sample of persons of Mexican origin to be used by other scholars. The general model that provides the framework for the substantive research treats ethnic identification, identity, and consciousness as intervening variables that directly influence four sets of mental health outcomes (mental health status including personal efficacy and self-esteem, utilization of services, social mobility aspirations for self and children, and action in behalf of the group) and are themselves influenced by individual-community contextual determinants as well as mediating the influence of these variables on the mental health outcomes. Three sets of research objectives within this general model guide the proposed research: 1) descriptive objectives in which the national sampling base is utilized for critically needed national and regional baseline data on the mental health outcomes, the identification, identity and consciousness intervening influences, and the individual-contextual determinants; 2) analytic objectives in which multivariate analyses of the interrelationships among these three sets of variables will be carried out; 3) comparative objectives in which the results from the study of Mexican origin persons will be compared with Census Bureau statistics and with results from two other Survey Research Center national sample surveys, one focused on group identification and one on mental health status and utilization of services.